The story of the Southwold Railway, the narrow gauge line that operated between Halesworth and Southwold from 1879 to 1929, is well known. Less familiar are the details of earlier failed proposals to link the towns with a Blyth valley railway.

The 1840s and 50s were very active decades for railway construction in East Anglia. Norwich was linked to Yarmouth in 1844, and to Brandon and Ely in 1845, with connections from there to London. Lowestoft was connected via Haddiscoe to the Norwich–Yarmouth line at Reedham in 1847. Then, in 1854, a line from Haddiscoe through Beccles to Halesworth was opened. What was by then the East Suffolk Railway extended its line from Halesworth to Woodbridge in 1859 giving, with the Eastern Counties Railway through Ipswich, a direct route to London.

In the twenty years before the Southwold Railway opened there were several attempts to promote a connection. In 1855 the Mayor of Southwold presented a petition to the ESR requesting that a branch be constructed to Southwold but this was rejected. In 1856 local businessmen and others met and resolved to form a committee and to approach the local gentry and MP for their support. Progress seems to have been slow because in September 1860 the Southwold Town Council was still at the stage of preparing a memorial for presentation to Sir Morton Peto (contractor and director of the ESR). There was disunity in the town on raising the necessary money and apparent concern that those of position and influence were not setting an example. The project cost was estimated to be £40,000 and Peto was said to be willing to "enter upon the necessary arrangements" if half could be subscribed. But Peto became further committed with the finances of the ESR. He was unable to continue support of the Southwold branch project, causing its failure.

By 1865, a Blyth Valley Railway had been surveyed and plans deposited with the county and relevant parishes. Southwold Corporation and Sir John Blois had agreed to sell land and it was proposed to seek an Act of Parliament. Public meetings and subscriptions notwithstanding, the Bill presented in 1866 failed. A subsequent Bill also failed and in 1871 it was reported that the Blyth Valley Railway proposals were again being revived under "influential London auspices". Either another new Bill failed or it was withdrawn and not until 1875 were new plans deposited. Meanwhile an 1872 Southwold–Halesworth Tramway proposal had also collapsed through lack of funds. The 1875 railway proposals were competing with the Southwold Railway. The narrow–gauge proposal succeeded but it too was dogged by disunity and lack of confidence in the local community. Its original local directors resigned and a London–based board developed the line.